Process for void creation in a helmet

ABSTRACT

This disclosure provides a method for making a helmet comprising a cavity between the outer shell and energy management layers.

TECHNICAL FIELD

This disclosure relates to a helmet comprising a cavity between the outer shell and energy management layers and a method for making and using the same.

BACKGROUND

Protective headgear and helmets have been used in a wide variety of applications and across a number of industries including sports, athletics, construction, mining, military defense, and others, to prevent damage to a user's head and brain. Damage and injury to a user can be prevented or reduced by helmets that prevent hard objects or sharp objects from directly contacting the user's head. Damage and injury to a user can also be prevented or reduced by helmets that absorb, distribute, or otherwise manage energy of an impact.

Different types of helmets have been used for different industries and for different applications. In addition to providing protection for the user's head, some helmets may also comprise components that protect or shield other vulnerable areas of a user, such as providing protection for a user's eyes, ears and mouth. Such protection can include features such as visors or eyeshields, sound dampening structures, and faceshields or faceguards. Helmets may also comprise features that augments a helmet's function beyond protection and may include features such as microphones, earphones, speakers, cameras, sensors, power supplies, microprocessors, transceivers or other electronics, and the like.

Previously, such features were typically attached to the exterior of the helmet, which has some disadvantages. First, the attachments may require piercing the outer shell of the helmet that may lead to weak areas. Second, the attachments may cause an imbalance of the helmet, leading to increased user fatigue and/or discomfort that may shorten the time in which a helmet can be worn. Third, the attachments may be relatively fragile and susceptible to damage when disposed on the exterior of the helmet. Fourth, attachments disposed on the exterior of the helmet project beyond the helmet body that may result in shapes that result in undesirable catch-points and/or decreased aerodynamic performance.

Accordingly, it is desirable to provide helmets in which features can be disposed in cavities between the outer shell of the helmet and internal energy management layers and methods for making such helmets.

SUMMARY OF THE DISCLOSED SUBJECT MATTER

In one aspect, disclosed is a method for preparing a cavity in a helmet, the method comprising:

forming a rigid sheet having a first surface on a first side of the sheet and a second surface on the opposed side of the sheet and a flange extending away from the first surface wherein the first surface and the flange provide a portion of the boundary of the cavity;

applying a layer comprising a foam composition to the second surface of the rigid sheet to provide a first assembly comprising the rigid sheet and a first foam layer;

disposing the first assembly in an outer shell of a helmet body, wherein the flange contacts the inner surface of the outer shell to define a separation of the inner surface of the outer shell into a first portion and a second portion, and the flange, first surface of the rigid sheet and the first portion of the inner surface of the outer shell form a boundary of a void in a desired shape of the cavity;

applying a second layer of a foam composition to the second portion of the inner surface of the outer shell and the first foam layer of the first assembly to provide a helmet body having a cavity between the outer shell and the first and second foam layers.

Embodiments of the method include the following, alone or in any combination.

The method wherein the cavity is disposed in a region of the helmet body corresponding to a brow region of a user wearing the helmet.

The method wherein the rigid sheet is formed in an arcuate configuration wherein the first surface is convex, the second surface is concave and the flange is disposed on an edge of the rigid sheet separating the first surface and the second surface and extends away from the first surface in the convex direction.

The method further comprising attaching at least one first additional component to the rigid sheet prior to applying the first foam layer.

The method wherein the at least one first additional component comprises a brow snap.

The method wherein the first foam layer is applied to a surface of the brow snap proximate to the second surface of the rigid sheet.

The method further comprising disposing at least one second additional component in the void prior to applying the second foam layer.

The method wherein the at least one second additional component comprises pivot mechanisms for a visor or eyeshield.

The method wherein the pivot mechanisms are disposed in the void in a region of the helmet body corresponding to a region of a user wearing the helmet proximate to the temporal regions of the user.

The method wherein the rigid sheet comprises polycarbonate.

The method wherein the foam composition of the first foam layer and the foam composition of the second foam layer independently comprise expanded polypropylene (EPP), expanded polystyrene (EPS), expanded polyurethane (EPU), or expanded polyolefin (EPO).

The method of claim 1 wherein forming the rigid sheet comprises vacuum forming, thermal forming, or a combination thereof.

The method of claim 1 wherein applying the first foam layer or the second foam layer comprises in-molding.

In another aspect, disclosed is a helmet comprising a helmet body comprising a cavity, the helmet body comprising

an outer shell;

an assembly disposed within the outer shell comprising

a rigid sheet having a first surface on a first side of the sheet and a second surface on the opposed side of the sheet and a flange extending away from the first surface wherein the first surface and the flange provide a portion of the boundary of the cavity; and a layer comprising a foam composition applied to the second surface of the rigid sheet;

wherein the flange contacts the inner surface of the outer shell to define a separation of the inner surface of the outer shell into a first portion and a second portion, and the flange, first surface of the rigid sheet and the first portion of the inner surface of the outer shell form a boundary of a void in a desired shape of the cavity; and

a second layer of a foam composition applied to the second portion of the inner surface of the outer shell and the first foam layer of the assembly to provide a helmet body having a cavity between the outer shell and the first and second foam layers.

Embodiments of the helmet include the following, alone or in any combination.

The helmet wherein the cavity is disposed in a region of the helmet body corresponding to a brow region of a user wearing the helmet.

The helmet wherein the rigid sheet is formed in an arcuate configuration wherein the first surface is convex, the second surface is concave and the flange is disposed on an edge of the rigid sheet separating the first surface and the second surface and extends away from the first surface in the convex direction.

The helmet further comprising at least one first additional component attached to the rigid sheet of the assembly.

The helmet wherein the at least one first additional component comprises a brow snap.

The helmet wherein the first foam layer is applied to a surface of the brow snap proximate to the second surface of the rigid sheet.

The helmet further comprising at least one second additional component disposed in the cavity.

The helmet wherein the at least one second additional component comprises pivot mechanisms for a visor or eyeshield.

The helmet wherein the pivot mechanisms are disposed in the cavity in a region of the helmet body corresponding to a region of a user wearing the helmet proximate to the temporal regions of the user.

The helmet wherein the rigid sheet comprises polycarbonate.

The helmet wherein the foam composition of the first foam layer and the foam composition of the second foam layer independently comprise expanded polypropylene (EPP), expanded polystyrene (EPS), expanded polyurethane (EPU), or expanded polyolefin (EPO).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a rigid sheet polycarbonate sheet having a first surface on a first side of the sheet and a second surface on the opposed side of the sheet and a flange extending away from the first surface defining a portion of desired cavity geometry, according to an exemplary embodiment of the disclosed subject matter.

FIG. 2 shows the rigid sheet of FIG. 1 with an additional component attached thereto, according to an exemplary embodiment of the disclosed subject matter.

FIG. 3 shows a foam layer applied to the rigid sheet and additional component of FIG. 2 to form a subassembly, according to an exemplary embodiment of the disclosed subject matter.

FIG. 4 shows at least one second additional component disposed in the portion of the cavity defined by the subassembly shown in FIG. 3 to provide a second subassembly, according to an exemplary embodiment of the disclosed subject matter.

FIG. 5A shows the second subassembly positioned within the outer shell (transparent shell in this image), creating a void in the shape of the desired cavity between the rigid sheet and the outer shell, according to an exemplary embodiment of the disclosed subject matter.

FIG. 5B shows a section view of a helmet with the second subassembly positioned within the outer shell, according to an exemplary embodiment of the disclosed subject matter.

FIG. 5C shows the same view as FIG. 5A wherein the outer shell is non-transparent, according to an exemplary embodiment of the disclosed subject matter.

FIG. 6A shows a second foam energy management layer applied to a portion of the interior of the outer shell (transparent shell in this image) and the first foam layer, trapping the second subassembly in place, according to an exemplary embodiment of the disclosed subject matter.

FIGS. 6B and 6C show section views of a helmet with the second foam energy management layer applied to a portion of the interior of the outer shell and the first foam layer, trapping the second subassembly in place, according to an exemplary embodiment of the disclosed subject matter.

FIG. 6D shows the same view as FIG. 6A wherein the outer shell is non-transparent, according to an exemplary embodiment of the disclosed subject matter.

FIGS. 7A and 7B show views of a helmet with a shield installed in a stored (up) position and a deployed (down) position, respectively, according to an exemplary embodiment of the disclosed subject matter.

FIGS. 8A and 8B show section views of a helmet with a shield installed in a stored (up) position and a deployed (down) position, respectively, according to an exemplary embodiment of the disclosed subject matter.

DETAILED DESCRIPTION

This disclosure, its aspects and implementations, are not limited to the specific helmet or material types, or other system component examples, or methods disclosed herein. Many additional components, manufacturing and assembly procedures known in the art consistent with helmet manufacture are contemplated for use with particular implementations from this disclosure. Accordingly, for example, although particular implementations are disclosed, such implementations and implementing components may comprise any components, models, types, materials, versions, quantities, and/or the like as is known in the art for such systems and implementing components, consistent with the intended operation.

The word “exemplary,” “example,” or various forms thereof are used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as “exemplary” or as an “example” is not necessarily to be construed as preferred or advantageous over other aspects or designs. Furthermore, examples are provided solely for purposes of clarity and understanding and are not meant to limit or restrict the disclosed subject matter or relevant portions of this disclosure in any manner. It is to be appreciated that a myriad of additional or alternate examples of varying scope could have been presented, but have been omitted for purposes of brevity.

While this disclosure includes a number of embodiments in many different forms, there is shown in the drawings and will herein be described in detail, particular embodiments with the understanding that the present disclosure is to be considered as an exemplification of the principles of the disclosed methods and systems, and is not intended to limit the broad aspect of the disclosed concepts to the embodiments illustrated.

Unless otherwise explicitly indicated, as used herein the terms “internal”, “inner” and “inside” indicate a relative position towards the helmet portion which is or would be closer to the wearer's head. Unless otherwise explicitly indicated, as used herein the terms “exterior”, “outer” and “external” indicate a relative position towards the helmet portion which is or would be closer to the outside of a helmet which is or would be away from the wearer's head. Similarly, terms such as “front”, “forward”, “rear”, “rearward”, “side”, “right”, “left”, “bottom”, “lower”, “top”, “upper”, “raised”, “brow”, “crown”, and the like refer to portions of a helmet or mechanisms therein relative to the helmet as worn by a user of the helmet.

This disclosure provides a device, apparatus, system, and method for providing a helmet or protective head gear that includes an outer shell and an inner energy absorbing layer, such as foam, that can be used for a cyclist, football player, hockey player, baseball player, lacrosse player, polo player, climber, auto racer, motorcycle rider, motocross racer, skier, snowboarder or other snow or water athlete, sky diver or any other athlete in a sport. Other industries also use protective headwear, such that individuals employed in other industries and work such as construction workers, soldiers, fire fighters, pilots, or types of work and activities can also use or be in need of a safety helmet, where similar technologies and methods can also be applied. Each of the above listed sports, occupations, or activities can use a helmet that includes either single or multi-impact rated protective material base that is typically, though not always, covered on the outside by a decorative cover and includes comfort material on at least portions of the inside, usually in the form of comfort padding.

Generally, protective helmets, such as the protective helmets listed above, can comprise an outer shell and an inner energy-absorbing or energy management material. For convenience, protective helmets can be generally classified as either in-molded helmets or hard shell helmets. In-molded helmets can comprise one layer, or more than one layer, including a thin outer shell, an energy-absorbing layer or impact liner, and a comfort liner or fit liner. Hard-shell helmets can comprise a hard outer shell, an impact liner, and a comfort liner. The hard outer shell can be formed by injection molding and can include Acrylonitrile-Butadiene-Styrene (ABS) plastics or other similar or suitable material. The outer shell for hard-shell helmets is typically made hard enough to resist impacts and punctures, and to meet the related safety testing standards, while being flexible enough to deform slightly during impacts to absorb energy through deformation, thereby contributing to energy management. Hard-shell helmets can be used as skate bucket helmets, motorcycle helmets, snow and water sports helmets, football helmets, batting helmets, catcher's helmets, hockey helmets, and can be used for BMX riding and racing. While various aspects and implementations presented in the disclosure focus on embodiments comprising hard-shell helmets or helmets comprising an outer shell, the disclosure also relates and applies to other helmets, applications, and embodiments in which the principles and features discussed herein can be advantageously applied. As such, a helmet comprising a cavity as disclosed herein can be employed wherever a conventional helmet is used to take advantage of the additional benefits described herein.

FIGS. 1 through 8B show exemplary embodiments of a method or process for preparing a cavity in a helmet. These figures show components present in each step of the process generally from the same viewpoint as if the viewer is looking into the interior of a helmet prepared according to the process from the front. In these embodiments, the cavity is configured to be in the brow (forehead) and temporal regions of the helmet, but this is not limiting. Cavities can be configured in any locus of the helmet by the method disclosed herein. Additional or alternative locations for cavities in a helmet prepared by this method can include one or both of the temporal regions, one or both of the ear regions, one or both of the sides, the brow, the crown, or the rear of the helmet, individually or in any combination. In other embodiments, a helmet comprising a chin bar (a “closed face” helmet) may additionally or alternatively comprise a cavity disposed near a user's mouth when the helmet is worn.

The method for preparing a cavity in a helmet comprises, as a first step, forming a rigid sheet having a first surface on a first side of the sheet and a second surface on the opposed side of the sheet and a flange extending away from the first surface wherein the first surface and the flange provide a portion of the boundary of the cavity as described further below. FIG. 1 shows an exemplary embodiment of a rigid sheet 100 formed in this step. The rigid sheet 100 has a first surface 101 on a first side of the sheet and a second surface 102 on the opposed side of the sheet and a flange 103 extending away from the first surface. The rigid sheet is configured to be disposed inside an outer shell of a helmet body as described in greater detail below.

As used herein, the term “rigid” refers to a material of sufficient stiffness that is does not easily bend, stretch, or twist or otherwise deform during the method for preparing a helmet with a cavity described herein. The rigid sheet can comprise plastics, including polycarbonate (PC), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS), polyethylene (PE), polyvinyl chloride (PVC), vinyl nitrile (VN), as well as resin, fiber, fiberglass, carbon fiber, Kevlar, or other suitable material. Preferably, the rigid sheet comprises polycarbonate. The rigid sheet can be stamped, injection molded, vacuum formed, thermoformed or formed by another suitable process. Preferably, the rigid sheet is formed by vacuum forming, thermoforming or a combination thereof. The rigid sheet may have a thickness of about 0.5 to 1 mm.

FIG. 1 shows a rigid sheet 100 for an exemplified method wherein the cavity is disposed in a region of the helmet body corresponding to a brow region of a user wearing the helmet. In this embodiment, the rigid sheet 100 is formed in an arcuate configuration wherein the first surface 101 is convex, the second surface is concave 102 and the flange 103 is disposed on an edge of the rigid sheet 100 separating the first surface 101 and the second surface 102 and extends away from the first surface 101 in the convex direction.

Optionally, the method may further comprise attaching at least one first additional component to the rigid sheet. FIG. 2 shows the rigid sheet of FIG. 1 with an additional component attached thereto, according to an exemplary embodiment of the disclosed subject matter. In this embodiment, a brow snap 201 is attached to rigid sheet 100. The brow snap 201 is configured to provide a lower margin of the assembled helmet in the brow area above the eyes of a user wearing the helmet. The brow snap is configured generally as a strip of material, such as nylon or polyoxymethylene (Delrin®), in an arcuate configuration. As shown in FIG. 2, the brow snap 201 comprises a flange 202 on the concave surface of the brow snap that is configured to face the interior of the helmet when assembled. The flange 202 shown is fenestrated, with a first row of perforations 202 a and a second row of perforations 202 b separated by narrow bars. As described below, the flange is configured to facilitate attaching an applied foam layer to the brow snap. The brow snap can be held in place by the geometric configuration of the sheet 100 and brow snap 201. Optionally, the additional component may be held in place by friction, mechanical means such as slots, flanges cleats, cutouts, and/or tabs, fasteners such as clips or screws, snaps, rivets, hog rings, or hook and loop fasteners, or other interlocking surfaces, features, or portions, or adhesives such as a permanent adhesive, pressure sensitive adhesive (PSA), foam-core adhesive, tape, or two-sided tape.

The method then comprises applying a layer comprising a foam composition to the second surface of the rigid sheet to provide a first assembly comprising the rigid sheet and a first foam layer. FIG. 3 shows a foam layer 301 applied to the rigid sheet 100 and brow snap 201 of FIG. 2 to form a subassembly, according to an exemplary embodiment of the disclosed subject matter. The foam layer 301 is applied to the second surface 102 and the contiguous surface of the flange 103. As shown in FIG. 3, the foam layer 301 covers the first row of perforations 202 a (not shown, compare to FIG. 2) of flange 202, while leaving the second row of perforations 202 b exposed. The first row of perforations 202 a are embedded in the foam layer 301, thereby holding it in place. The foam layer 301 can be formed of one or more layers of an energy-absorbing material made of foam, or other suitable energy-absorbing material or impact liner to absorb, deflect, or otherwise manage energy and to contribute to energy management for protecting a wearer during impacts. The foam layer 301 can comprise, without limitation, expanded polypropylene (EPP), expanded polystyrene (EPS), expanded polyurethane (EPU), or expanded polyolefin (EPO), vinyl nitrile (VN), or other suitable material that can manage absorb, or deflect energy from an impact by bending, flexing, crushing, or cracking. In addition to contributing to energy management, the foam layer 301 also provides bulking to the rigid sheet 100 that can contribute to limit its deformation during subsequent steps in the process. Preferably, foam layer 301 comprises EPP, EPS, EPU, or EPO; notably EPS. The foam layer is preferably applied to the rigid sheet by in-molding in a void between the second surface 102 of rigid sheet 100 and a mold component proximate to the second surface 102 and configured to provide a desired shape of the foam layer 301. Preferably, the shape of the foam layer 301 is substantially concave in relation to the interior of a helmet made by the disclosed method and conforms closely to the second surface 102 of the rigid sheet 100. Preferably, the foam layer 301 has substantially uniform thickness, such about 5 to 8 mm, for example about 6 mm. Preferably, the in-molded foam layer 301 has some adherence to the rigid sheet 100 and the interior of the helmet.

Optionally, the method may further comprise disposing at least one second additional component in the void or volume partially bounded by the first surface 101 and the flange 103 of the rigid sheet 100. FIG. 4 shows at least one second additional component disposed in the portion of the cavity defined by the subassembly shown in FIG. 3 to provide a second subassembly, according to an exemplary embodiment of the disclosed subject matter. The at least one additional second component can be held in place by complementary geometric configurations of the sheet 100 and the additional component(s). Optionally, the additional component(s) may be held in place by friction, mechanical means such as slots, flanges, cleats, cutouts, and/or tabs, fasteners such as clips, screws, snaps, rivets, hog rings, or hook and loop fasteners, or other interlocking surfaces, features, or portions, or adhesives such as a permanent adhesive, pressure sensitive adhesive (PSA), foam-core adhesive, tape, or two-sided tape.

In the embodiment shown, the at least one second additional component comprises pivot mechanisms 401 a and 401 b for a visor or eyeshield. As shown in FIG. 4, the pivot mechanisms are disposed in the void in a region of the helmet body corresponding or proximate to the temporal regions a user wearing the helmet. The pivot mechanisms provide the ability to pivot a visor or eyeshield between a first position in which it is stored in the cavity of the helmet and a second position in which it deployed to protect or shield the eyes of the user of the helmet. Pivot mechanism 401 a may comprise a first generally triangular member 402 a and a second, smaller generally triangular member 403 a rotatably engaged to member 402 a via a pivot point 404 a. The outer surface of flange 405 a on member 402 a is configured to engage the inner surface of flange 103 of rigid sheet 100 to facilitate proper positioning of the pivot mechanism in the void. Flange 405 a also provides stops so that rotation of member 403 a is limited to be between a first position and a second position. A visor or eyeshield (not shown) can be releasably attached to member 403 a by engaging attachment region 406 a with a complementary shaped attachment member. Member 403 a is depicted in the first position in FIG. 4 such that an attached visor or eyeshield is stored within the cavity at least partially bounded by first surface 101 and flange 103 of rigid sheet 100. Pivot mechanism 401 b is configured similarly, wherein members 402 b and 403 b are mirror images of members 402 a and 403 a.

The method then comprises disposing the assembly 400 prepared as in FIGS. 1-4 in an outer shell of a helmet body, wherein the flange contacts the inner surface of the outer shell to define a separation of the inner surface of the outer shell into a first portion and a second portion, and the flange, first surface of the rigid sheet and the first portion of the inner surface of the outer shell form a boundary of a void in a desired shape of the cavity, as shown in FIGS. 5A-5C.

The outer shell 501 can be made of a flexible, semi-flexible, or rigid material, and can comprise plastics, including polycarbonate (PC), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS), polyethylene (PE), polyvinyl chloride (PVC), vinyl nitrile (VN), as well as resin, fiber, fiberglass, carbon fiber, Kevlar, or other suitable material. The outer shell 501 can be stamped, in-molded, injection molded, vacuum formed, or formed by another suitable process. The outer shell 501 can also provide a smooth aerodynamic finish, a decorative finish, or both, for improved performance, improved aesthetics, or both. As a non-limiting example, the outer shell 501 can be ABS that is formed by injection molding.

The outer shell 501 can also include a number of rivets, screws, or other fastening devices 520 that can be made of metal, plastic, or other suitable material that can be attached to the outer shell 501 for securing straps to the helmet 500, for securely and releasably coupling the helmet 500 to a head of a user wearing the helmet 500. The rivets 520 can be placed in various portions of the outer shell 501 including proximate to a user's ear, in a temple tab and/or a collar tab. For example the temple tab and collar tab can be portions of the outer shell 501 located at an outer edge of the outer shell 501 adjacent a recess or opening for a user's ear.

One or more vents 530 can be formed as openings or voids through the helmet 500, including through the outer shell 501, to provide increased ventilation and airflow through the helmet. In the embodiment shown, vent 530 comprises a slit that provides fluid communication through the liner 601 (see subsequent Figures) and the outer shell 501 to the exterior of the helmet 500. This embodiment is not limiting, and other vent amounts and placements are envisioned.

While the outer shell 501 is, for convenience, referred to throughout this disclosure as an “outer” shell, the term outer is used to describe a relative position of the outer shell 501 with respect to the rigid sheet 100 and the user's head when the helmet 500 is worn by the user. Additional layers, liners, covers, or shells can be formed outside of the outer shell 501 because the outer shell 501 can be, but does not need to be, the outermost layer of the helmet 500.

The assembly 400 can be disposed inside the outer shell 501 such that flange 103 and foam layer 301 contact the inner surface of outer shell 501 substantially along their entire length, thereby defining a boundary 505 separating the inner surface of the outer shell into two portions, a first portion 510 and a second portion 511.

In some embodiments, the assembly 400 can be held in place geometrically and/or by friction with outer shell 501. In some embodiments, complementary positioning features such as slots, holes, depressions, projections, tabs, flanges and the like on assembly 400 and/or outer shell 501 can facilitate disposition of assembly 400 within outer shell 501. In some embodiments, assembly 400 can be held temporarily inside outer shell 501 by a clamp, jig and/or mold during subsequent application of a foam layer as described below.

In the embodiment shown in FIGS. 5A-5C, first portion 510 is disposed generally in the brow and temporal regions of the helmet 500. First surface 101, flange 103, brow snap 201 and first portion 510 define the boundary of a void or cavity in helmet 500 (shown shaded in FIG. 5C). The second portion 511 is disposed generally in the crown, side and back regions of the outer shell 501. As discussed above, this disposition is not limiting and the portions 510 and 511 can be disposed anywhere on outer shell 501 such that first portion 510 in combination with surface 101 and flange 103 defines a portion of the boundary of a void in helmet 500 and second portion 511 defines the region of the helmet 500 that does not comprise the void.

In the embodiment shown in the Figures, outer shell 501 is depicted as a unitary shell, but this is not limiting. In other embodiments, the outer shell may comprise at least one cut-out or opening proximate to the void. In such embodiments, the cut-out or opening could be configured with a panel that covers the void but may be at least partially releasable to allow access to component(s) contained within the void. For example, the panel may be hingedly attached to a portion of the opening, releasably snap fit in the opening, and/or removably fastened in the opening with fasteners such as clips, screws, snaps, rivets, hog rings, or hook and loop fasteners.

FIG. 6A shows a second foam energy management layer 601 applied to a portion 511 of the interior of the outer shell (transparent shell in this image) and the first foam layer 301, trapping the second subassembly 400 in place.

FIGS. 6B and 6C show section views of a helmet with the second foam energy management layer 601 applied to a portion 511 of the interior of the outer shell (transparent shell in this image) and the first foam layer, trapping the second subassembly 400 in place.

FIG. 6D shows the same view as FIG. 6A wherein the outer shell is non-transparent.

The foam layer 601 can be formed of one or more layers of an energy-absorbing material made of foam, or other suitable energy-absorbing material or impact liner to absorb, deflect, or otherwise manage energy and to contribute to energy management for protecting a wearer during impacts. The foam layer 601 can comprise, without limitation, expanded polypropylene (EPP), expanded polystyrene (EPS), expanded polyurethane (EPU), or expanded polyolefin (EPO, vinyl nitrile (VN), or other suitable material that can manage absorb, or deflect energy from an impact by bending, flexing, crushing, or cracking. Preferably, foam layer 601 comprises EPP, EPS, EPU, or EPO; notably EPS or EPP, or more notably EPS. The composition of foam layer 601 may be the same as or different from the composition of foam layer 601.

For convenience, foam layer 601 is referred to as being disposed at a position that is “inner” or within the outer shell 501 and is positioned more closely to the user's head. However, additional layers, liners, covers, or padding can be additionally disposed inside of the foam layer 601, because the foam layer 601 can be, but does not need to be, the innermost layer of the helmet 500.

The foam layer 601 is preferably applied to the inside of the outer shell 501 by in-molding in a void defined by the inner surface of the outer shell 101 and foam layer 301 and a mold component proximate to the inner surface of the outer shell 501 configured to provide a desired shape of the foam layer 601. The foam layer 601 can be formed with any desirable shape including an outer surface that contacts and follows a contour of the inner surface of the outer shell 501 in at least a portion of region 511 and an inner surface that contacts and follows a contour of a head of a user. The foam layer 601 may have some adherence to the outer shell but it may be held in place primarily by the geometric configurations of the outer shell 501 and the foam layer 601.

The foam layer 601 comprises at least a portion of energy-management liner(s) for the helmet 500. In the embodiment shown in FIGS. 6A to 6D, foam layer 601 is shown for simplicity of illustration as a unitary foam monolayer covering a substantial portion of the inner surface of the outer shell 501 in the region 511 corresponding to the sides, crown and back of the helmet. However, this is not limiting.

In some embodiments, an energy management liner may comprise multiple components. In such embodiments, foam layer 601 is disposed adjacent to a first portion of region 511 proximate to the foam layer 301 and not proximate to a second portion of region 511 that may comprise for example portions of the sides, crown or back of helmet 500.

For example, the use of multiple pieces for the energy management layers of the helmet 500 can also allow for the foam liner 601 to include foam or energy management materials of multiple densities or to be multi-density. For example, a segment of the liner 601 can comprise a first or outer layer, laminum, or stratum of a first density that will be positioned closest to the outer shell 501, and a second or inner layer, laminum, or stratum of a second density that will be positioned closer to the user's head and farther from the outer shell 501 than the first layer. The first layer can have a density that is greater than or less than a density of the second layer. Alternatively, different individual pieces or segments of the foam liner 601 can comprise a single density that is different from other individual pieces to form an alternative embodiment of a multi-density liner.

Attachment of all or part of the foam liner 601 to the outer shell 501 can be done in such a way that the portions of the foam liner 601 is removable from, and is disposed within, the outer shell 501, as part of a glueless assembly. As used herein, a glueless assembly can mean that all or an entirety of the foam liner 601, or that a portion less than all of the foam liner 601, can be attached to the outer shell 501 without glue, chemical attachment or bonding, an adhesive, permanent adhesive, pressure sensitive adhesive (PSA), foam-core adhesive, tape, two-sided tape, mounting foam adhesive, or other similar attachment, which for convenience are hereinafter collectively referred to as an adhesive. The adhesive, if optionally used, can be disposed at any location along the inner surface of the outer shell 501, including along or near a lower edge of the outer shell 501.

In some embodiments, an adhesive can be used to indirectly couple the foam liner 601 to the outer shell 501, such as by using an adhesive to attach hook and loop fasteners, a clip, cleat, cutout, tab, snap, rivet, hog ring, or other suitable mechanical fasteners to the outer shell 501 and to the foam liner 601, such that the foam liner 601, or portion thereof, can be releasably coupled to the outer shell 501 and be easily removed from the outer shell 501 because adhesive is not directly attached to foam liner 601 or the outer shell 501. However, in some embodiments, the foam liner 601 can also be coupled to the outer shell 501 without hook and loop fasteners or other similar chemical or mechanical attachment, and instead rely exclusively on the connection or interface between a locking piece of the foam liner 601 and a locking mechanism disposed on the inner surface of the outer shell 501. In some instances, the helmet 500 can retain the foam liner 601 coupled to the outer shell 501 by relying on both the connection or interface between the locking piece of the foam liner 601 and the locking mechanism of the outer shell 501, as well as a curved or retaining geometry of the lower edge of the outer shell 501, such an inward curve of a temple tab or a collar tab, or other similar curve or retaining structure of the outer shell 501.

By forming the foam liner 601 of a plurality of different pieces, such as one or more of side pieces, top pieces, and locking piece, the foam liner 601 can provide increased design flexibility with respect to conventional one-body or monolithic protective helmets. Increased design flexibility can be achieved by forming the foam liner 601 comprising shapes, geometric forms, and orientations that would be difficult to accomplish with a single body liner. Constraints restricting shapes, geometric forms, and orientations of a single body liner include constraints for injecting foam or energy-absorbing material into a mold, constraints of removing the molded foam or energy-absorbing material from the mold, and constraints of machining or removing the single body liner from a template or standard blank of material such as a block of energy-absorbing material. For example, use of multiple interlocking body pieces for the foam liner 601 can allow for helmet shapes, geometric forms, and orientations that would be difficult or impossible to remove or pull from a 1-piece mold. As a non-limiting example, increased design flexibility with respect to helmet shape for the helmet 500 can include a helmet comprising a curvature or profile that follows a contour of the occipital region or occipital curve of user's head. Furthermore, increased design flexibility can be achieved because forming the foam liner 601 can simplify assembly of energy-absorbing material, such as at an EPS press.

Multi-layer foam liner 601 can comprise two or more layers, including three layers, four layers, or any number of layers. As a non-limiting example, a multi-layer liner may comprise three layers: an outer-layer, a middle-layer, and an inner-layer. Other additional layers, such as a comfort liner layer disposed inside the multi-layer liner 601 and adjacent the inner-layer can also be included.

Furthermore, multiple liner layers can provide boundary conditions at the interfaces of the multiple liner layers that also serve to deflect energy and beneficially manage energy dissipation at various conditions, including low-energy impacts, mid-energy impacts, and high-energy impacts. In some embodiments, a multi-layer foam liner 601 can be formed with one or more slots, gaps, channels, or grooves that can provide or form boundary conditions at the interface between a multi-layer foam liner 601 and the air or other material that fills or occupies the slots. The boundary conditions created by slots can serve to deflect energy and change energy propagation through the helmet to beneficially manage energy dissipation for a variety of impact conditions.

In the following paragraphs, a non-limiting example of a multi-layer foam liner 601 is described with respect to an outer-layer, a middle-layer, and an inner-layer. While the outer-layer is described below as being adapted for high-energy impacts, the middle-layer is described below as being adapted for low-energy impacts, and the inner-layer is described as being adapted for mid-energy impacts, in other embodiments, the ordering or positioning of the various layers could be varied. For example, the outer-layer can also be adapted for low-energy as well as for mid-energy impacts. Furthermore, the middle-layer can be adapted for high-energy impacts as well as for mid-energy impacts. Similarly, the inner-layer can be adapted for high-energy impacts as well as for low-energy impacts. Additionally, more than one layer can be directed to a same or similar type of energy management. For example, two layers of multi-layer liner 601 can be adapted for a same level of energy management, such as high-energy impacts, mid-energy impacts, or low-energy impacts.

According to one possible arrangement, the outer-layer can be formed as a high-energy management material and can comprise a material that is harder, denser, or both, than the other layers within the multi-layer foam liner 601. A material of the outer-layer can comprise EPS, EPP, Vinyl Nitrile (VN), or other suitable material. In an embodiment, the outer-layer can comprise a material with a density in a range of about 30-90 grams/liter (g/L), or about 40-70 grams/liter (g/L), or about 50-60 g/L. Alternatively, the outer-layer can comprise a material with a density in a range of about 20-50 g/L. By forming the outer-layer with a material that is denser than the other layers, including middle-layer and inner-layer, the denser outer-layer can manages high-energy impacts while being at a distance farther from the user's head. As such, less dense or lower-energy materials will be disposed closer to the user's head and will be more yielding, compliant, and forgiving with respect to the user's head during impacts. In an embodiment, the outer-layer can comprise a thickness in a range of about 5-25 mm, or about 10-20 mm, or about 15 mm, or about 10-15 mm.

The middle-layer can be disposed or sandwiched between the outer-layer and the inner-layer. The middle-layer, when formed as a low-energy management layer, can be formed of EPO, polyester, polyurethane, D3o (a dilatant non-Newtonian fluid comprising an energy-absorbing material comprising closed-cell polyurethane foam composite and several additives including polyborodimethylsiloxane), Poron® (open cell microcellular polyurethane foam), an air bladder, helium, a comfort liner material, or other suitable material. The middle-layer can comprise a density in a range of about 5-30 g/L, about 10-20 g/L, or about 15 g/L. The middle-layer can have a thickness less than a thickness of both the inner-layer and outer-layer (both separately and collectively). In an embodiment, the middle-layer can comprise a thickness in a range of about 3-9 mm, or about 5-7 mm, or about 6 mm, or about 4 mm.

The inner-layer can be formed as a medium-energy or mid-energy management material and can comprise a material that is softer, less dense, or both, than the material of other layers, including the outer-layer. For example, the inner-layer can be made of an energy absorbing material such as EPS, EPP, VN, or other suitable material. In an embodiment, the inner-layer can be made of EPS with a density in a range of about 20-40 g/L, about 25-35 g/L, or about 30 g/L. Alternatively, the inner-layer can be made of EPP with a density of about 30-50 g/L, or about 35-45 g/L, or about 20-40 g/L, or about 40 g/L. Alternatively, the inner-layer can comprise a material with a density in a range of about 20-50 g/L. Forming the inner-layer comprising a density within the ranges indicated above, as part of multi-layer liner, provides better performance during mid-energy impact testing than conventional helmets and helmets without an inner-layer or a mid-energy liner. By forming the inner-layer as being less dense than the outer-layer and denser than the middle-layer, the inner-layer as part of the multi-layer liner can advantageously manage low-energy impacts. In an embodiment, the inner-layer can comprise a thickness in a range of about 5-25 mm, 10-20 mm, or about 10-15 mm.

Additional components can be added to complete a helmet prepared according to this disclosure. In the embodiments shown herein, the void is configured to receive and store an eyeshield or visor. FIGS. 7A and 7B show views of a helmet with a shield installed in a stored (up) position and a deployed (down) position, respectively.

As shown in FIGS. 7A and 7B, additional foam energy management components can be added to the helmet 500. Foam liner(s) 602 can be disposed in the region of the helmet proximate to a user's ear when wearing a helmet. Foam liner 602 can be in-molded in the helmet or molded outside of the helmet and then installed. Extension 601 a on foam liner 601 (see FIGS. 6A, 6B and 6D) provides an engagement surface or locking mechanism to hold the foam liner 602 in place.

Attachment of all or part of the foam liner 602 to the outer shell 501 can be done in such a way that the portions of the foam liner 602 is removable from, and is disposed within, the outer shell 501, as part of a glueless assembly. As used herein, a glueless assembly can mean that all or an entirety of the foam liner 602, or that a portion less than all of the foam liner 602, can be attached to the outer shell 501 without glue, chemical attachment or bonding, an adhesive, permanent adhesive, pressure sensitive adhesive (PSA), foam-core adhesive, tape, two-sided tape, mounting foam adhesive, or other similar attachment, which for convenience are hereinafter collectively referred to as an adhesive. The adhesive, if optionally used, can be disposed at any location along the inner surface of the outer shell 501, including along or near a lower edge of the outer shell 501.

In some embodiments, an adhesive can be used to indirectly couple the foam liner 602 to the outer shell 501, such as by using an adhesive to attach hook and loop fasteners, a clip, cleat, cutout, tab, snap, rivet, hog ring, or other suitable mechanical fasteners to the outer shell 501 and to the foam liner 602, such that the foam liner 602, or portion thereof, can be releasably coupled to the outer shell 501 and be easily removed from the outer shell 501 because adhesive is not directly attached to foam liner 601 or the outer shell 501. However, in some embodiments, the foam liner 602 can also be coupled to the outer shell 501 without hook and loop fasteners or other similar chemical or mechanical attachment, and instead rely exclusively on the connection or interface between a locking piece of the foam liner 602 and/or a locking mechanism disposed on the inner surface of the outer shell 501 or the foam liner 601, such as 601 a.

Similarly, a neckroll pad 603 can be installed on helmet 500.

FIG. 7A shows a shield 700 a engaged to the pivot mechanisms 401 a and 401 b in an “up” position, wherein it is stored within void 510 of helmet 500.

FIG. 7B shows a shield 700 b engaged to the pivot mechanisms 401 a and 401 b and deployed out of the void 510 in a “down” position, wherein it is disposed in front of a user's eyes when wearing the helmet.

FIG. 8A shows a cut-away view of helmet 500 with a shield 700 a engaged to the pivot mechanisms 401 a and 401 b in an “up” position, wherein it is stored within void 510 of helmet 500. In the embodiment illustrated, vent channels 604 direct air flow form the brow area of the helmet to vent 530 at the rear of the helmet 500, but this is not limiting.

FIG. 8B shows a cut-away view of helmet 500 with a shield 700 b engaged to the pivot mechanisms 401 a and 401 b and deployed out of the void 510 in a “down” position, wherein it is disposed in front of a user's eyes when wearing the helmet.

A non-limiting example of the helmet 500 may comprise an optional comfort padding, comfort liner, or fit liner. The comfort liner can be disposed within the space created for the user's head by the liner 601, and can also be disposed adjacent, and in contact with, an inner surface of the liner 601. The comfort liner can be made of textiles, plastic, foam, polyester, nylon, or other suitable materials. The comfort liner can be formed of one or more pads of material that can be joined together, or formed as discrete components, that can be coupled to the helmet 500. The comfort liner can be releasably or permanently attached to the helmet 500, such as to the liner 601, using an adhesive, permanent adhesive, PSA, foam-core adhesive, tape, two-sided tape, mounting foam adhesive, fastener, clip, cleat, cutout, tab, snap, rivet, hog ring, or hook and loop fasteners, or other interlocking surfaces, features, or portions. As such, the comfort liner can provide a cushion and improved fit for the wearer of the helmet 500.

The preceding description provides exemplary embodiments of a method or process for preparing a cavity in a helmet wherein the cavity is configured to be in the brow (forehead) and temporal regions of the helmet and configured for storing an eyeshield or visor, but this is not limiting and a cavity can ber located in any portion of the helmet. Additional or alternative locations for cavities in a helmet prepared by this method can include one or both of the temporal regions, one or both of the ear regions, one or both of the sides, the brow, the top, the crown, or the rear of the helmet, individually or in any combination.

In example embodiments, cavities on one or both of the sides and/or top of the helmet can be configured to contain camera(s) or other optical devices. In addition or alternative to a visor, a head-up display can be stored in and deployed from a cavity in the brow region of the helmet. Cavities proximate to the ear regions can contain earphones, speakers, or sound-dampening structures or materials. Cavities in one or more locations in the helmet may be configured to contain electronics, such as processors, transceivers, power supplies such as batteries, etc. to enable network and wireless connectivity and control other accessories of a helmet.

In embodiments, a helmet comprising a chin bar (a “full-face” helmet) may additionally or alternatively comprise a cavity disposed near a user's mouth when the helmet is worn to contain, for example, a microphone.

Where the above examples, embodiments and implementations reference examples, it should be understood by those of ordinary skill in the art that other helmet and manufacturing devices and examples could be intermixed or substituted with those provided as virtually any component consistent with the intended operation of a method, system, or implementation may be utilized. Accordingly, for example, although particular component examples may be disclosed, such components may be comprised of any shape, size, style, type, model, version, class, grade, measurement, concentration, material, weight, quantity, and/or the like consistent with the intended purpose, method and/or system of implementation. In places where the description above refers to particular embodiments of helmets, it should be readily apparent that a number of modifications may be made without departing from the spirit thereof and that these embodiments and implementations may be applied to other to gear and equipment technologies as well. Accordingly, the disclosed subject matter is intended to embrace all such alterations, modifications, and variations that fall within the spirit and scope of the disclosure and the knowledge of one of ordinary skill in the art. The presently disclosed embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. 

1. A method for preparing a cavity in a helmet, the method comprising: forming a rigid sheet having a first surface on a first side of the sheet and a second surface on the opposed side of the sheet and a flange extending away from the first surface wherein the first surface and the flange provide a portion of the boundary of the cavity; applying a layer comprising a foam composition to the second surface of the rigid sheet to provide a first assembly comprising the rigid sheet and a first foam layer; disposing the first assembly in an outer shell of a helmet body, wherein the flange contacts the inner surface of the outer shell to define a separation of the inner surface of the outer shell into a first portion and a second portion, and the flange, first surface of the rigid sheet and the first portion of the inner surface of the outer shell form a boundary of a void in a desired shape of the cavity; applying a second layer of a foam composition to the second portion of the inner surface of the outer shell and the first foam layer of the first assembly to provide a helmet body having a cavity between the outer shell and the first and second foam layers.
 2. The method of claim 1 wherein the cavity is disposed in a region of the helmet body corresponding to a brow region of a user wearing the helmet.
 3. The method of claim 1 wherein the rigid sheet is formed in an arcuate configuration wherein the first surface is convex, the second surface is concave and the flange is disposed on an edge of the rigid sheet separating the first surface and the second surface and extends away from the first surface in the convex direction.
 4. The method of claim 1 further comprising attaching at least one first additional component to the rigid sheet prior to applying the first foam layer.
 5. The method of claim 4 wherein the at least one first additional component comprises a brow snap.
 6. The method of claim 5 wherein the first foam layer is applied to a surface of the brow snap proximate to the second surface of the rigid sheet.
 7. The method of claim 1 further comprising disposing at least one second additional component in the void prior to applying the second foam layer.
 8. The method of claim 7 wherein the at least one second additional component comprises one or more pivot mechanisms for a visor or eyeshield.
 9. The method of claim 8 wherein the one or more pivot mechanisms are disposed in the void in a region of the helmet body corresponding to a region of a user wearing the helmet proximate to the temporal regions of the user.
 10. The method of claim 1 wherein the rigid sheet comprises polycarbonate.
 11. The method of claim 1 wherein the foam composition of the first foam layer and the foam composition of the second foam layer independently comprise expanded polypropylene (EPP), expanded polystyrene (EPS), expanded polyurethane (EPU), or expanded polyolefin (EPO).
 12. The method of claim 1 wherein forming the rigid sheet comprises vacuum forming, thermal forming, or a combination thereof.
 13. The method of claim 1 wherein applying the first foam layer or the second foam layer comprises in-molding.
 14. A helmet comprising a helmet body comprising a cavity, the helmet body comprising an outer shell; an assembly disposed within the outer shell comprising a rigid sheet having a first surface on a first side of the sheet and a second surface on the opposed side of the sheet and a flange extending away from the first surface wherein the first surface and the flange provide a portion of the boundary of the cavity; and a layer comprising a foam composition applied to the second surface of the rigid sheet; wherein the flange contacts the inner surface of the outer shell to define a separation of the inner surface of the outer shell into a first portion and a second portion, and the flange, first surface of the rigid sheet and the first portion of the inner surface of the outer shell form a boundary of a void in a desired shape of the cavity; and a second layer of a foam composition applied to the second portion of the inner surface of the outer shell and the first foam layer of the assembly to provide a helmet body having a cavity between the outer shell and the first and second foam layers.
 15. The helmet of claim 14 wherein the cavity is disposed in a region of the helmet body corresponding to a brow region of a user wearing the helmet.
 16. The helmet of claim 14 wherein the rigid sheet is formed in an arcuate configuration wherein the first surface is convex, the second surface is concave and the flange is disposed on an edge of the rigid sheet separating the first surface and the second surface and extends away from the first surface in the convex direction.
 17. The helmet of claim 14 further comprising at least one first additional component attached to the rigid sheet of the assembly.
 18. The helmet of claim 17 wherein the at least one first additional component comprises a brow snap.
 19. The helmet of claim 18 wherein the first foam layer is applied to a surface of the brow snap proximate to the second surface of the rigid sheet.
 20. The helmet of claim 14 further comprising at least one second additional component disposed in the cavity.
 21. The helmet of claim 20 wherein the at least one second additional component comprises pivot mechanisms for a visor or eyeshield.
 22. The helmet of claim 21 wherein the pivot mechanisms are disposed in the cavity in a region of the helmet body corresponding to a region of a user wearing the helmet proximate to the temporal regions of the user.
 23. The helmet of claim 14 wherein the rigid sheet comprises polycarbonate.
 24. The helmet of claim 14 wherein the foam composition of the first foam layer and the foam composition of the second foam layer independently comprise expanded polypropylene (EPP), expanded polystyrene (EPS), expanded polyurethane (EPU), or expanded polyolefin (EPO). 